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Abstract: This article describes the production of nanodisperse xerogel and powders (average CSR size of 9 nm) in the ZrO2–Y2O3–Al2O3system by coprecipitation of hydroxides. A strong highly porous ceramic has been produced from the initial powder with the composition of [(ZrO2)0.97(Y2O3)0.03]0.8(Al2O3)0.2with pore forming additives using patented solid phase sintering. Using Doppler sonography, the volume of blood flow in arteriolas and capillaries has been estimated 150 and 250 days after implantation of plates. Therefore, the microcirculatory Doppler sonography seems to be a promising intravital method of estimating blood flow in the zone of plates from biocompatible nonresorbable material and, probably, inside the plates. It has been found that the ceramic plates based on zirconium dioxide in the body of experimental animals do not result in a negative reaction of animal’s body. The in vivo experimental results make it possible to state that the obtained bioceramic based on zirconium dioxide is a promising material for endoprosthetics.

Abstract—: By the joint crystallization of solutions of nitrate salts, fine powders of La1 – xSrxNiO3, La1 ‒xSrx-CoO3, and La1 –xSrxFe0.7Ni0.3O3(x= 0.30 and 0.40) are synthesized. They have a specific pore volume of 0.018–0.035 cm3/g and a specific surface area of 15–31 m2/g. On their basis, ceramic nanomaterials of a given composition with CSR ~ 64–70 nm (1300°С) are obtained. The physicochemical properties of the obtained ceramic are studied; it is revealed that the ceramic is a solid solution with open porosity in a range of 17–30% and a high value of the relative density of 94%. In terms of their physicochemical properties (open porosity, density, coefficient of thermal expansion), the obtained ceramic materials are promising as solid oxide cathodes for intermediate-temperature fuel cells.

Abstract: Mesoporous nanosized aerogels, xerogels, and powders in the ZrO2–Y2O3–CeO2and ZrO2‒Y2O3–Al2O3systems have been obtained by liquid-phase synthesis methods. The thermolysis, phase composition, and textural features of the synthesized materials have been studied. It has been found that the predominance of Lewis acid sites (LASs) on the surface of their particles indicates its lower hydroxylation and, as a consequence, a lower degree of agglomeration of the obtained materials.

Measurements have been made on the nonstationary temperature distribution in a channel containing saturated superfluid helium with local stepped heat input. A numerical method has been developed, which incorporates the variable thermophysical parameters for the helium.